Has anyone paid much attention to the fatty acid compositions of
calorie-restricted diets? Most people tend to reduce calories by cutting
down on fats, and particularly saturated ones.
There is evidence that dietary fatty acid composition affects mitochondrial
membrane fatty acid composition. The polyunsaturated FA content of the
mitochondrial inner membrane correlates with its proton leak (and may be
causal?). It has been suggested that proton leak serves as a sink for
redox energy to prevent ROS production by the respiratory chain.
Less saturates = more polyunsaturates = higher proton leak = less ROS =
slower ageing.
Has anyone measured proton leak (or if not, state 4 resp' rates) in mito's
from CR mice?
Is higher proton leak in aged animals a compensatory mechanism to cope with
having a more sloppy respiratory chain that leaks more ROS?
Does this apply to "reduced food intake diets", in which the composition of
the food is the same, just less of it is eaten. This is distinctly
different from caloric restriction (who thought of that name?). What
effect does just eating less food have on mitochondrial FA composition?
Any thoughts?
PSB
______________________________________________
Dr. Paul S. Brookes. (brookes at uab.edu)
UAB Department of Pathology, G004 Volker Hall
1670 University Blvd., Birmingham AL 35294 USA
Tel (001) 205 934 1915 Fax (001) 205 934 1775
http://peir.path.uab.edu/brookes